devel/rubygem-ffi: Switch time_t and suseconds_t types to long
When using rubygem-ethon there is sometimes the following error:
Ethon::Errors::Select (An error occured on select: 22)
This is caused by a wrong type definition in rubygem-ffi, which
the patch corrects.
Issue: https://github.com/typhoeus/ethon/issues/98